780909845 has 16 divisors (see below), whose sum is σ = 944073840. Its totient is φ = 620089344.

The previous prime is 780909769. The next prime is 780909853. The reversal of 780909845 is 548909087.

It can be written as a sum of positive squares in 8 ways, for example, as 20584369 + 760325476 = 4537^2 + 27574^2 .

It is a cyclic number.

It is not a de Polignac number, because 780909845 - 2¹⁴ = 780893461 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 780909793 and 780909802.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 729971 + ... + 731039.

It is an arithmetic number, because the mean of its divisors is an integer number (59004615).

Almost surely, 2^780909845 is an apocalyptic number.

It is an amenable number.

780909845 is a deficient number, since it is larger than the sum of its proper divisors (163163995).

780909845 is a wasteful number, since it uses less digits than its factorization.

780909845 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2024.

The product of its (nonzero) digits is 725760, while the sum is 50.

The square root of 780909845 is about 27944.7641786436. The cubic root of 780909845 is about 920.8741868041.

The spelling of 780909845 in words is "seven hundred eighty million, nine hundred nine thousand, eight hundred forty-five".